Do PV systems have to be grid-tied to be modeled?  The Tech Procedures give no clear guidance in this area. Nor does the Hot2000 Guide.  I understand that in the case where the solar panels and power-storage are just there as a backup, it should not be modeled, as it does not affect the load.  However, when there is a house with 2 separate electrical systems, one grid-tied the other self generated, should it be modeled?  

Yes I have a real-world case like this right now...

It only took 100 days to get this answer from NRCan Program Support:

"Hello Jeffrey,

Regardless of whether the solar PV system is connected to house or grid, the solar PV system must be included in the ERS model when one is present on the property. ..."

Of course I could point out the obvious that this does not consider backup systems  which are used more like a generator than as a supplement to daily power demand.  Yes we have seen that scenario here.

All good, though, I get the point.